Utilizing a multiphase reactor for the conversion of biomass to produce substituted furans

ABSTRACT

The present disclosure provides methods to produce substituted furans (e.g., halomethylfurfural, hydroxymethylfurfural, and furfural), by acid-catalyzed conversion of biomass using a gaseous acid in a multiphase reactor, such as a fluidized bed reactor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/805,321, filed Jul. 21, 2015, which is a continuation of U.S. patentapplication Ser. No. 14/124,240, filed Jun. 6, 2012 (now U.S. Pat. No.9,126,964, issued on Sep. 8, 2015), which is the U.S. National StageApplication of PCT/US2012/041087, filed internationally on Jun. 6, 2012,which claims priority to U.S. Provisional Patent Application No.61/495,324 filed Jun. 9, 2011, all of which are incorporated herein byreference in their entireties.

FIELD

The present disclosure relates generally to the conversion of biomassinto biofuels and chemicals. In particular, the present disclosurerelates to the production of substituted furans (e.g.,halomethylfurfural, hydroxymethylfurfural, and furfural) byacid-catalyzed conversion of biomass containing glycans (e.g.,cellulose) and/or heteroglycans (e.g., hemicellulose), using a gaseousacid in a multiphase reactor.

BACKGROUND

Efforts to reduce dependence on fossil fuels for transportation fuel andas feedstock for industrial chemicals have been undertaken for decades,with a particular focus on enabling economic feasibility of renewablefeedstock. Heightened efforts are being made to more effectively utilizerenewable resources and develop “green” technologies, due to continuedlong-term increases in the price of fuel, increased environmentalconcerns, continued issues of geopolitical stability, and renewedconcerns for the ultimate depletion of fossil fuels.

Conventional biofuel production from renewable feedstock employs atwo-step process. In the first step, fermentable sugars are producedfrom biomass, typically by enzymatic saccharification. In the secondstep, the sugars are fermented into biofuels or chemicals. This two-stepprocess, however, presents several technical challenges.

For example, biomass needs to be pretreated before hydrolysis can takeplace to produce sugars. Digestibility of cellulose in biomass ishindered by various physicochemical, structural and compositionalfactors. Pretreating biomass helps digest the cellulose andhemicellulose fractions of biomass by breaking down the lignin structureand disrupting the crystalline structures of cellulose andhemicellulose. This makes the biomass more accessible to hydrolysis forproducing sugars used in subsequent fermentation. Common pretreatmentsknown in the art involve, for example, mechanical treatment (e.g.,shredding, pulverizing, grinding), concentrated acid, dilute acid, SO₂,alkali, hydrogen peroxide, wet-oxidation, steam explosion, ammonia fiberexplosion (AFEX), supercritical CO₂ explosion, liquid hot water, andorganic solvent treatments. These pretreatment options, however, areoften expensive and technically difficult to implement on a commercialscale.

Moreover, acid conversion of biomass to produce the sugars oftenencounter mass transfer limitations that may reduce overall reactionyields and limit control of product selectivity. Grinding may improvemass transfer rates by reducing particle size; however, forsolution-phase systems, the biomass particle size may be approximatelyone micron or less before mass transfer is no longer rate-limiting.Grinding biomass to this particle size may often be energy-intensive andcommercially impractical.

Solution-phase hydrochloric acid (HCl)-catalyzed hydrolysis of cellulosemay offer high glucose yields, but commercialization has beenchallenging. Technical considerations that may be expensive to addresson a commercial scale include the high concentrations of aqueous HCl(≥40%) used for effective conversion and throughput under conditions ofmoderate temperature hydrolysis; high energy requirements for HClrecycling due to formation of boiling azeotropes of HCl and water atconcentrations of 20 wt %; additional energy requirements to recover HClsolvent from the slurry cake formed from lignin that is saturated withHCl-rich solutions; and the use of large glass-lined reactors, which areoften expensive, due to the high corrosiveness of HCl.

Once biomass is hydrolyzed to form sugars, challenges also exist topurify the resulting sugars and to remove hydrolysis by-products (e.g.,acetate and formate). For example, if the cellulose used as a startingmaterial is not pure, the sugars produced may be harder to isolate.

Substituted furans (e.g., halomethylfurfural, hydroxymethylfurfural, andfurfural) produced from biomass may be converted into furanicderivatives used as biofuels and diesel additives, as well as a broadrange of chemicals and plastic materials. For example,5-(chloromethyl)furfural can be converted into 2,5-dimethylfuran, whichmay be used as a biofuel. Additionally, 5-(chloromethyl)furfural can beconverted into 5-(ethoxymethyl)furfural, which is a combustible materialthat may be used as a diesel additive or kerosene-like fuel. Furanicderivatives, however, are currently underutilized to produce chemicalcommodities because the commercial production methods are noteconomical.

The production of 5-(chloromethyl)furfural and 5-(hydroxymethyl)furfuralfrom cellulose was first described in the early 1900s; however, slowkinetics and harsh reaction conditions make this method of biofuelproduction commercially unattractive.

What is needed in the art is a method to directly prepare biofuels andchemicals from biomass, thereby addressing some of the challengesassociated with the conventional two-step process involving enzymaticsaccharification and fermentation. What is also needed in the art is amethod to prepare substituted furans (e.g., halomethylfurfural,hydroxymethylfurfural, and furfural) from biomass containing celluloseand/or hemicellulose in an efficient and cost-effective way. Once thesesubstituted furans are produced, they can serves as intermediates thatcan be converted into to furanic derivatives such as biofuels, dieseladditives, and plastics.

SUMMARY

The present disclosure addresses this need by providing processes toproduce substituted furans (e.g., halomethylfurfural,hydroxymethylfurfural, and furfural) by acid-catalyzed conversion ofbiomass using a gaseous acid in a multiphase reactor. The processesdisclosed herein make it possible to directly produce substituted furans(e.g., halomethylfurfural, hydroxymethylfurfural, and furfural) from thecellulose and/or hemicellulose in biomass in a way that minimizes theneed for pretreating the biomass.

The present disclosure provides fast and cost-effective processesutilizing a multiphase reactor to convert a wide range of cellulosicfeedstock into substituted furans (e.g., halomethylfurfural,hydroxymethylfurfural, and furfural). Other compounds, such as levulinicacid and formic acid, may also be produced by the processes. Theprocesses employ a gaseous acid to catalyze the conversion of glycans(e.g., cellulose) and/or heteroglycans (e.g., hemicellulose) tosubstituted furans, such as hydroxymethylfurfural, chloromethylfurfural,and furfural—all within a single unit operation. Thus, the processesdescribed herein open up an efficient industrial process to chemicalssuch as dimethylfuran, ethoxymethylfurfural, and furan dicarboxylicacid.

In one aspect, provided is a process for producing a substituted furanin a multiphase reactor, by: feeding biomass and a gaseous acid into amultiphase reactor; and mixing the biomass and the gaseous acid in thepresence of a proton donor and a solvent to form a reaction mixture,under conditions suitable to produce a substituted furan, in which thereaction mixture has less than 10% by weight of water.

In some embodiments, the process further includes separating gaseousacid from the reaction mixture using a solid-gas separator; and dryingthe separated gaseous acid. The solid-gas separator may be a cyclone, afilter, or a gravimetric system.

In some embodiments that can be combined with the preceding embodiment,the process further includes feeding the dried gaseous acid into themultiphase reactor. In one embodiment, the multiphase reactor is afluidized bed reactor.

In some embodiments that can be combined with any of the precedingembodiments, the gaseous acid is a halogen-based mineral acid or ahalogen-based organic acid. In certain embodiments, the gaseous acid isgaseous hydrochloric acid. In other embodiments, the gaseous acid hasless than 10% by weight of water. In one embodiment, the gaseous acid isdry. In certain embodiments, the gaseous acid is continuously fed intothe multiphase reactor.

In some embodiments that can be combined with any of the precedingembodiments, the biomass includes glycans, heteroglycans, lignin,inorganic salts, cellular debris, or any combination thereof. In certainembodiments, the biomass is continuously fed into the multiphasereactor. In other embodiments, the biomass has less than 10% by weightof water.

In some embodiments that can be combined with any of the precedingembodiments, the proton donor is a Lewis acid. Suitable Lewis acids mayinclude, for example, lithium chloride, sodium chloride, potassiumchloride, magnesium chloride, calcium chloride, zinc chloride, aluminumchloride, boron chloride, or any combination thereof. In otherembodiments, the proton donor has less than 10% by weight of water.

In some embodiments that can be combined with any of the precedingembodiments, the solvent is selected from dichloromethane, ethylacetate,hexane, cyclohexane, benzene, toluene, diethyl ether, tetrahydrofuran,acetone, dimethyl formamide, dimethyl sulfoxide, acetonitrile, methanol,ethanol, isopropanol, n-propanol, n-butanol, chloroform, dichloroethane,trichloroethane, furfural, furfuryl alcohol, supercritical carbondioxide, and any combination thereof. In some embodiments, the solventis dry. In other embodiments, the solvent has less than 10% by weight ofwater.

In other embodiments that may be combined with any of the precedingembodiments, the pressure in the multiphase reactor is between 0.001 atmand 350 atm. In one embodiment, the pressure in the multiphase reactoris between 0.001 atm and 100 atm. In another embodiment, the pressure inthe multiphase reactor is between 0.001 atm and 10 atm. In yet anotherembodiment, the pressure in the multiphase reactor is between 1 atm and50 atm. In yet other embodiments that may be combined with any of thepreceding embodiments, the temperature in the multiphase reactor isbetween 50° C. and 500° C. In one embodiment, the temperature in themultiphase reactor is between 100° C. and 400° C. In another embodiment,the temperature in the multiphase reactor is between 100° C. and 350° C.In yet another embodiment, the temperature in the multiphase reactor isbetween 150° C. and 300° C. In yet another embodiment, the temperaturein the multiphase reactor is between 200° C. and 250° C.

In some embodiments that may be combined with any of the precedingembodiments, the substituted furan may include halomethylfurfural,hydroxymethylfurfural, furfural, or any combination thereof. In certainembodiments, the substituted furan is halomethylfurfural. In certainembodiments, the substituted furan is hydroxymethylfurfural. In certainembodiments, the substituted furan is furfural. In some embodiments, thehalomethylfurfural is chloromethylfurfural, iodomethylfurfural,bromomethylfurfural, or fluoromethylfurfural. In one embodiment, thehalomethylfurfural is chloromethylfurfural. In other embodiments, thehalomethylfurfural is 5-(chloromethyl)furfural, 5-(iodomethypfurfural,5-(bromomethyl)furfural, or 5-(fluoromethyl)furfural. In anotherembodiment, the halomethylfurfural is 5-(chloromethyl)furfural. In someembodiments that may be combined with any of the preceding embodiments,the reaction mixture further includes levulinic acid, formic acid,alkylfurfural, or any combination thereof. In certain embodiments, thereaction mixture includes levulinic acid. In certain embodiments, thereaction mixture includes formic acid. In certain embodiments, thereaction mixture includes alkylfurfural. In certain embodiments, thealkylfurfural may be optionally substituted. In one embodiment, thealkylfurfural is methylfurfural.

Another aspect of the disclosure provides a process for producing asubstituted furan in a multiphase reactor by: feeding biomass into amultiphase reactor; feeding a gaseous acid into the multiphase reactor,in which the gaseous acid has less than about 10% by weight of water;and mixing the biomass and the gaseous acid to form a reaction mixturethat includes a substituted furan. In one embodiment, the processfurther includes separating gaseous acid from the reaction mixture usinga solid-gas separator, and drying the separated gaseous acid. Thesolid-gas separator may be a cyclone, a filter, or a gravimetric system.In another embodiment that may be combined with any of the precedingembodiments, the process further includes feeding the dried gaseous acidinto the multiphase reactor. This recycles the gaseous acid used in theprocess to produce the crude mixture.

In some embodiments that can be combined with any of the precedingembodiments, the process further includes adding a proton donor to thereaction mixture. In certain embodiments, the proton donor is a Lewisacid. Suitable Lewis acids may include, for example, lithium chloride,sodium chloride, potassium chloride, magnesium chloride, calciumchloride, zinc chloride, aluminum chloride, boron chloride, or anycombination thereof. In other embodiments, the proton donor has lessthan 10% by weight of water.

In other embodiments that may be combined with any of the precedingembodiments, the process further includes combining the reaction mixturewith a solvent, in which the solvent solubilizes the substituted furan,and in which the combining produces a solution that includes thesubstituted furan; and separating the solution. The solvent may includedichloromethane, ethyl acetate, hexane, cyclohexane, benzene, toluene,diethyl ether, tetrahydrofuran, acetone, dimethyl formamide, dimethylsulfoxide, acetonitrile, methanol, ethanol, isopropanol, n-propanol,n-butanol, chloroform, dichloroethane, trichloroethane, furfural,furfuryl alcohol, supercritical carbon dioxide, or any combinationthereof. In some embodiments that may be combined with any of thepreceding embodiments, the solvent is dichloromethane, ethyl acetate,supercritical carbon dioxide, or any combination thereof. In someembodiments, the solvent is dry. In other embodiments, the solvent hasless than 10% by weight of water.

In some embodiments that may be combined with any of the precedingembodiments, the solution may be separated from residual solids using afilter or a membrane system. In yet other embodiments that may becombined with any of the preceding embodiments, the process furtherincludes distilling the solution to obtain the substituted furan. Thisdistillation also produces a separated solvent. In some embodiments thatmay be combined with any of the preceding embodiments, the processfurther includes combining the separated solvent with a second reactionmixture. As such, the solvent may be recaptured.

In one embodiment that may be combined with any of the precedingembodiments, the multiphase reactor is a fluidized bed reactor. In someembodiments that may be combined with any of the preceding embodiments,the gaseous acid is a halogen-based mineral acid or a halogen-basedorganic acid. In certain embodiments, the gaseous halogen-based mineralacid is hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid(HBr), or hydrofluoric acid (HF). In one embodiment, the gaseoushalogen-based mineral acid is hydrochloric acid (HCl). In someembodiments that may be combined with any of the preceding embodiments,the gaseous acid is continuously fed into the multiphase reactor.

In other embodiments that may be combined with any of the precedingembodiments, the biomass includes glycans, heteroglycans, lignin,inorganic salts, cellular debris, or any combination thereof.Particulates may also be present in the biomass, including for exampleclay, silica, humic materials, or any combination thereof. In yetanother embodiment that may be combined with any of the precedingembodiments, the biomass is continuously fed into the multiphasereactor. In other embodiments, the biomass has less than 10% by weightof water.

In other embodiments that may be combined with any of the precedingembodiments, the pressure in the multiphase reactor is between 0.001 atmand 350 atm. In one embodiment, the pressure in the multiphase reactoris between 0.001 atm and 100 atm. In another embodiment, the pressure inthe multiphase reactor is between 0.001 atm and 10 atm. In yet anotherembodiment, the pressure in the multiphase reactor is between 1 atm and50 atm. In yet other embodiments that may be combined with any of thepreceding embodiments, the temperature in the multiphase reactor isbetween 50° C. and 500° C. In one embodiment, the temperature in themultiphase reactor is between 100° C. and 400° C. In another embodiment,the temperature in the multiphase reactor is between 100° C. and 350° C.In yet another embodiment, the temperature in the multiphase reactor isbetween 150° C. and 300° C. In yet another embodiment, the temperaturein the multiphase reactor is between 200° C. and 250° C.

In some embodiments that may be combined with any of the precedingembodiments, the substituted furan may include halomethylfurfural,hydroxymethylfurfural, furfural, and any combination thereof. In certainembodiments, the substituted furan is halomethylfurfural. In certainembodiments, the substituted furan is hydroxymethylfurfural. In certainembodiments, the substituted furan is furfural. In some embodiments, thehalomethylfurfural is chloromethylfurfural, iodomethylfurfural,bromomethylfurfural, or fluoromethylfurfural. In one embodiment, thehalomethylfurfural is chloromethylfurfural. In other embodiments, thehalomethylfurfural is 5-(chloromethyl)furfural, 5-(iodomethypfurfural,5-(bromomethyl)furfural, or 5-(fluoromethyl)furfural. In anotherembodiment, the halomethylfurfural is 5-(chloromethyl)furfural. In someembodiments that may be combined with any of the preceding embodiments,the reaction mixture further includes levulinic acid, formic acid,alkylfurfural, or any combination thereof. In certain embodiments, thereaction mixture includes levulinic acid. In certain embodiments, thereaction mixture includes formic acid. In certain embodiments, thereaction mixture includes alkylfurfural. In certain embodiments, thealkylfurfural may be optionally substituted. In one embodiment, thealkylfurfural is methylfurfural.

Another aspect of the disclosure provides a process for producinghalomethylfurfural, hydroxymethylfurfural, furfural, or any combinationthereof in a multiphase reactor, by: feeding biomass into a multiphasereactor; feeding a gaseous acid into the multiphase reactor, in whichthe gaseous acid has less than about 10% by weight of water; and mixingthe biomass and the gaseous acid to form a reaction mixture thatincludes halomethylfurfural, hydroxymethylfurfural, furfural, or anycombination thereof. In one embodiment, the process further includesseparating gaseous acid from the reaction mixture using a solid-gasseparator, and drying the separated gaseous acid. The solid-gasseparator may be a cyclone, a filter, or a gravimetric system. Inanother embodiment that may be combined with any of the precedingembodiments, the process further includes feeding the dried gaseous acidinto the multiphase reactor. This recycles the gaseous acid used in theprocess to produce the crude mixture.

In some embodiments that can be combined with any of the precedingembodiments, the process further includes adding a proton donor to thereaction mixture. In certain embodiments, the proton donor is a Lewisacid. Suitable Lewis acids may include, for example, lithium chloride,sodium chloride, potassium chloride, magnesium chloride, calciumchloride, zinc chloride, aluminum chloride, boron chloride, or anycombination thereof. In other embodiments, the Lewis acid has less than10% by weight of water.

In other embodiments that may be combined with any of the precedingembodiments, the process further includes combining the reaction mixturewith a solvent, in which the solvent solubilizes the halomethylfurfural,hydroxymethylfurfural, furfural, or any combination thereof, and inwhich the combining produces a solution that includes thehalomethylfurfural, hydroxymethylfurfural, furfural, or any combinationthereof; and separating the solution. The solvent may includedichloromethane, ethyl acetate, hexane, cyclohexane, benzene, toluene,diethyl ether, tetrahydrofuran, acetone, dimethyl formamide, dimethylsulfoxide, acetonitrile, methanol, ethanol, isopropanol, n-propanol,n-butanol, chloroform, dichloroethane, trichloroethane, furfural,furfuryl alcohol, supercritical carbon dioxide, or any combinationthereof. In some embodiments that may be combined with any of thepreceding embodiments, the solvent is dichloromethane, ethyl acetate,supercritical carbon dioxide, or any combination thereof. In someembodiments, the solvent is dry. In other embodiments, the solvent hasless than 10% by weight of water.

In some embodiments that may be combined with any of the precedingembodiments, the solution may be separated from residual solids using afilter or a membrane system. In yet other embodiments that may becombined with any of the preceding embodiments, the process furtherincludes distilling the solution to obtain the halomethylfurfural,hydroxymethylfurfural, furfural, or any combination thereof. Thisdistillation also produces a separated solvent. In some embodiments thatmay be combined with any of the preceding embodiments, the processfurther includes combining the separated solvent with a second reactionmixture. As such, the solvent may be recaptured.

In one embodiment that may be combined with any of the precedingembodiments, the multiphase reactor is a fluidized bed reactor. In someembodiments that may be combined with any of the preceding embodiments,the gaseous acid is a halogen-based mineral acid or a halogen-basedorganic acid. In certain embodiments, the gaseous halogen-based mineralacid is hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid(HBr), or hydrofluoric acid (HF). In one embodiment, the gaseoushalogen-based mineral acid is hydrochloric acid (HCl). In someembodiments that may be combined with any of the preceding embodiments,the gaseous acid is continuously fed into the multiphase reactor.

In other embodiments that may be combined with any of the precedingembodiments, the biomass includes glycans, heteroglycans, lignin,inorganic salts, cellular debris, or any combination thereof.Particulates may also be present in the biomass, including for exampleclay, silica, humic materials, or any combination thereof. In yetanother embodiment that may be combined with any of the precedingembodiments, the biomass is continuously fed into the multiphasereactor.

In other embodiments that may be combined with any of the precedingembodiments, the pressure in the multiphase reactor is between 0.001 atmand 350 atm. In one embodiment, the pressure in the multiphase reactoris between 0.001 atm and 100 atm. In another embodiment, the pressure inthe multiphase reactor is between 0.001 atm and 10 atm. In yet anotherembodiment, the pressure in the multiphase reactor is between 1 atm and50 atm. In yet other embodiments that may be combined with any of thepreceding embodiments, the temperature in the multiphase reactor isbetween 50° C. and 500° C. In one embodiment, the temperature in themultiphase reactor is between 100° C. and 400° C. In another embodiment,the temperature in the multiphase reactor is between 100° C. and 350° C.In yet another embodiment, the temperature in the multiphase reactor isbetween 150° C. and 300° C. In yet another embodiment, the temperaturein the multiphase reactor is between 200° C. and 250° C.

In some embodiments, the halomethylfurfural is chloromethylfurfural,iodomethylfurfural, bromomethylfurfural, or fluoromethylfurfural. In oneembodiment, the halomethylfurfural is chloromethylfurfural. In otherembodiments, the halomethylfurfural is 5-(chloromethyl)furfural,5-(iodomethyl)furfural, 5-(bromomethyl)furfural, or5-(fluoromethyl)furfural. In another embodiment, the halomethylfurfuralis 5-(chloromethyl)furfural. In some embodiments that may be combinedwith any of the preceding embodiments, the reaction mixture furtherincludes levulinic acid, formic acid, alkylfurfural, or any combinationthereof. In certain embodiments, the alkylfurfural may be optionallysubstituted. In one embodiment, the alkylfurfural is methylfurfural.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application can be best understood by reference to thefollowing description taken in conjunction with the accompanying drawingfigures, in which like parts may be referred to by like numerals:

FIG. 1 is an exemplary reaction scheme that shows the conversion ofcellulose and hemicellulose into 5-(chloromethyl)furfural,5-hydroxymethylfurfural, and furfural by acid-catalyzed hydrolysis anddehydration; and

FIG. 2 depicts a block diagram for an exemplary process of producingsubstituted furans (e.g., halomethylfurfural, hydroxymethylfurfural, andfurfural) in a multiphase reactor, in which the dotted lines representoptional inputs or steps.

DETAILED DESCRIPTION

The following description sets forth numerous exemplary configurations,processes, parameters, and the like. It should be recognized, however,that such description is not intended as a limitation on the scope ofthe present disclosure, but is instead provided as a description ofexemplary embodiments.

The following description relates to processes involving acid-catalyzedconversion of biomass to produce substituted furans, such ashalomethylfurfural, hydroxymethylfurfural, and furfural, by using amultiphase reactor.

Acid-Catalyzed Conversion of Biomass

Glycans and heteroglycans in biomass can be converted into substitutedfurans. In some embodiments, cellulose and hemicellulose in biomass canbe converted into halomethylfurfural, hydroxymethylfurfural, and/orfurfural in the presence of an acid. Other products, such as levulinicacid and formic acid, may also be produced in the reaction. The acidcleaves the glycosidic bond in glycans and heteroglycans to yield sugarand water by catalytic hydrolysis and dehydration of the cellulose andhemicellulose. The acid then reacts with the sugars to producesubstituted furans. In some embodiments, the acid cleaves the glycosidicbond in cellulose and hemicellulose to yield sugar and water bycatalytic hydrolysis and dehydration of the cellulose and hemicellulose.The acid then reacts with the sugars to produce halomethylfurfurals.

With reference to FIG. 1, in an exemplary process, cellulose 102 ishydrolyzed in the presence of a gaseous halogen-based mineral acid 104to produce hexose 106 (e.g., glucose, fructose), which then undergoesdehydration in the acidic environment to produce halomethylfurfural 108and hydroxymethylfurfural 110.

Given the acidic reaction conditions, however, halomethylfurfural 108and hydroxymethylfurfural 110 may rehydrate to produce levulinic acid112 and formic acid 114. Among the products formed from this exemplaryreaction, halomethylfurfurals are the preferred product because they aremore reactive intermediates for conversion into biofuels and biodieseladditives and derivative products, compared to the other co-products.

In addition to cellulose as a starting material, hemicellulose in thebiomass can also undergo hydrolysis. With reference to FIG. 1,hemicellulose 120 can be hydrolyzed to form hexose 106 and pentose 122(e.g., arabinose, xylose). Pentose 122 can be converted into furfural124.

It should be understood that additional components may be added to anyof the reactions in the exemplary reaction scheme depicted in FIG. 1.For example, in other exemplary embodiments, a proton donor, a solvent,a desiccant, or any combination thereof may be added to producehalomethylfurfural 108 and hydroxymethylfurfural 110 from cellulose 102in the presence of a gaseous halogen-based mineral acid 104.

The processes described herein employ various components, including amultiphase reactor, solid feedstock, and a gaseous acid, to carry outthe conversion of cellulose and/or hemicellulose to produce substitutedfurans.

The Multiphase Reactor

A multiphase reactor is a reactor vessel that can be used to carry outchemical reactions in two or more phases (i.e., solid, liquid, gas). Themultiphase reactor used in the processes described herein may be afluidized bed reactor or other multiphase reactors. By using amultiphase reactor for the processes described herein, a singlehigh-pressure, high-temperature operation unit for combined and rapidsingle-step may be used to directly convert sugars from glycans andheteroglycans into biofuels and chemicals. In some embodiments, themultiphase reactor may be used to directly convert sugars from celluloseand hemicellulose into biofuels and chemicals. Thus, the use of amultiphase reactors in the processes described herein may lead tooperation cost-savings since existing methods to produce biofuels andchemicals from cellulose and hemicellulose typically involve two steps:first, producing fermentable sugars from lignocellulose, and then,fermenting these sugars into biofuels and chemicals.

a) Fluidized Bed Reactors

In a fluidized bed reactor, a fluid (either a gas or a liquid) is passedthrough solid particles at high velocities to suspend the solidparticles, causing the solid particles to behave in a suspension. Thisphenomenon is known as fluidization.

A fluidized bed reactor may offer several advantages. For example,fluidization enables thorough and rapid mixing of the suspended solidsaround the bed, allowing for uniform heat transfer and uniform mixing,and eliminating hot spots within the reactor mixture. Moreover, thoroughand rapid mixing minimizes the need to pretreat biomass to access thecellulose and hemicellulose.

When a gas is used as the fluid in the reactor, high gas phasediffusivities overcome some of the mass transfer barriers. For example,the Schmidt number of gaseous hydrochloric acid is lower than that ofaqueous hydrochloric acid, allowing the reaction to proceed at a fasterrate. When the reaction is run at high temperatures, the increaseddiffusivity is further magnified due to low gas phase heat capacity.Thus, the combination of increased diffusivity and high reactiontemperatures can significantly reduce reaction times.

Further, the faster reaction rate also allows the use of smaller, moreaffordable reactors capable of processing the same throughput ofmaterial, which may decrease capital costs. Consequently, the size andcapacity of handling equipment for the reactors may also be reduced,which may further decrease capital costs. Energy costs may also belowered with the reduced heat capacity, which contributes to making theprocesses described herein more economically and commercially feasible.Moreover, increasing throughput as a result of faster reaction ratesaffords the ability to recycle unreacted materials. By optimizing thereaction rate and recycling unreacted materials, the reactions may bedriven to optimal conversion and selectivity, favoring reactions towardsthe substituted furans (e.g., halomethylfurfural andhydroxymethylfurfural), while minimizing the reactions towards otherproducts, such as levulinic acid and formic acid.

A fluidized bed reactor also allows for continuous operation, whichconfers a commercial advantage for scaling up reactions compared tobatch operations. The solid feed can be continuously introduced into thefluidized bed reactor by using an airlock feed valve. A fluidized bedreactor has the capacity of handling large volumes of biomass withminimal feedstock preparation. For example, the feedstock used in thistype of reactor only requires drying and grinding before introductioninto the reactor, thereby eliminating the need for expensive enzymaticpretreatments.

b) Other Multiphase Reactors

Other multiphase reactors may be used to achieve thorough and rapidmixing of the solids with gas. For example, plug-flow reactors may beused. Other methods of mixing may also be employed, such as mechanicalmixing and gravity. These methods of mixing may be independent of gasflow rates. For example, mechanically-driven method for mixing may beprovided by an auger or agitation system.

The Feedstock

The feedstock used in the processes described herein includes biomass.Biomass can be plant material made up of organic compounds relativelyhigh in oxygen, such as carbohydrates, and also contain a wide varietyof other organic compounds. Lignocellulosic biomass is a type of biomassthat is made up of cellulose and/or hemicellulose bonded to lignin inplant cell walls.

The feedstock may originate from various sources. For example, in someembodiments, the feedstock may originate from waste streams, e.g.,municipal wastewater, pulp waste, food processing plant waste,restaurant waste, yard waste, forest waste, biodieseltransesterification waste, and ethanol process waste. In otherembodiments, suitable feedstock may include corn stover, rice hulls,rice straw, wheat straw, paper mill effluent, newsprint, municipal solidwastes, wood chips, forest thinings, slash, miscanthus, switchgrass,sorghum, bagasse, manure, wastewater biosolids, green waste, andfood/feed processing residues. In yet other embodiments, the feedstockmay be fructose or glucose. Any combination of the feedstock describedabove may also be used as a starting material for the processesdescribed herein.

The processes described herein can handle feedstock that isheterogeneous in nature, without increasing the occurrence of sideproducts, such as alkoxymethylfurfurals that may be formed from cellulardebris containing nucleophilic alcohols. The biomass used may havematerials such as, for example, particulates, lignin, inorganic salts,and cellular debris. Particulates may include, for example, clays,silica, and humic materials. In some embodiments, the lignin content ofthe biomass may be less than or equal to about 60%. In some embodiments,inorganic salts may include sulfate or carbonate salts.

The biomass may further include glycans (e.g., cellulose, fructose,glucose, oligomeric starches) as well as fatty acids. It should also beunderstood, however, that although the processes described herein arewell-suited to handling heterogeneous feedstock, pure or relatively purecellulose and/or hemicellulose may be also used.

In some embodiments, the feedstock contains less than 10%, less than 9%,less than 8%, less than 7%, less than 6%, less than 5%, less than 4%,less than 3%, less than 2%, less than 1% water, less than 0.1%, lessthan 0.01%, or less than 0.001% (wt/wt basis). In yet other embodiments,the feedstock contains between 1-10%, between 2-10%, between 2-4%,between 1-2%, between 0.01-2%, or between 0.001-2% water (wt/wt basis).

The Gaseous Acid

The acid used in the processes described herein is in a gaseous state.As used herein, the term “gaseous acid” refers to any acid that can gointo the gaseous state.

In some embodiments, the gaseous acid is dry. As used herein, the term“dry” refers to a substance with a water content lower than itsazeotrope concentration.

In other embodiments, the gaseous acid contains less than 10%, less than9%, less than 8%, less than 7%, less than 6%, less than 5%, less than4%, less than 3%, less than 2%, less than 1% water, less than 0.1%, lessthan 0.01%, or less than 0.001% (wt/wt basis). In yet other embodiments,the gaseous acid contains between 1-10%, between 2-10%, between 2-4%,between 1-2%, between 0.01-2%, or between 0.001-2% water (wt/wt basis).The gaseous acid is undissociated when fed into the multiphase reactor,and dissociates upon adsorption to the glycans and/or heteroglycans inthe biomass.

The acid employed may either be halogen-based mineral acids orhalogen-based organic acids. In one embodiment, any halogen-basedmineral acid may be used. Examples may include hydrochloric acid (HCl),hydrofluoric acid (HF), hydrobromic acid (HBr), and hydroiodic acid(HI). In another embodiment, any halogen-based organic acid that caninduce hydration and ring cyclization to form the substituted furans mayalso be used. In some embodiments, any halogen-based organic acids thatcan induce hydration and ring cyclization to form the halomethylfurfuralmay be used. Suitable halogen-based organic acids may include, forexample, trifluoroacetic acid (TFA). In certain embodiments, ahalogen-based acid may be used.

The concentration of the gaseous acid used in the processes describedherein may vary. In some embodiments, the concentration of the gaseousacid is less than or equal to 8.7M. In other embodiments, theconcentration of the gaseous acid is less than or equal to 2.4M. Inother embodiments, the concentration of the gaseous acid is less than orequal to 0.2M. In other embodiments, the concentration of the gaseousacid is less than or equal to 0.02M. In other embodiments, theconcentration of the gaseous acid is between 0.0001M and 8.7M. In otherembodiments, the concentration of the gaseous acid is between 2.4M and8.7M. In other embodiments, the concentration of the gaseous acid isbetween 0.2M and 2.4M. In other embodiments, the concentration of thegaseous acid is between 0.02M and 0.2M. In other embodiments, theconcentration of the gaseous acid is between 0.0001M and 0.02M.

The processes described herein may further include separating thegaseous acid from the reaction mixture using a solid-gas separator, suchas for example a cyclone, a filter, or a gravimetric system.Additionally, the processes may further include drying the separatedgaseous acid, and returning the dried gaseous acid to the reactor. Insome embodiments, drying a substance refers to removing water from asubstance so that its water content is lower than its azeotropeconcentration. In other embodiments, drying a substance refers toremoving water from a substance so that its water content is less than10%, less than 9%, less than 8%, less than 7%, less than 6%, less than5%, less than 4%, less than 3%, less than 2%, less than 1% water, lessthan 0.1%, less than 0.01%, or less than 0.001% (wt/wt basis). In yetother embodiments, drying a substance refers to removing water from asubstance so that its water content is between 1-10%, between 2-10%,between 2-4%, between 1-2%, between 0.01-2%, or between 0.001-2% water(wt/wt basis).

The Proton Donor

A proton donor may be added to the reaction mixture. In someembodiments, the proton donor is a Lewis acid. In other embodiments, theproton donor is non-nucleophilic. In yet other embodiments, the protondonor may be soluble in the reaction mixture under the reactionconditions described herein. In yet other embodiments, the proton donormay have a pKa value less than the gaseous acid used in the reaction.The Lewis acid used as the proton donor may complex with the gaseousacid in the reaction to form a superacid. As used herein, a “superacid”is an acid with a pKa less than the pKa of pure sulfuric acid. Anycombinations of the proton donors described above may also be used.

In some embodiments, the proton donor may be selected from lithiumchloride, sodium chloride, potassium chloride, magnesium chloride,calcium chloride, zinc chloride, aluminum chloride, boron chloride, andany combination thereof. In one embodiment, the proton donor may becalcium chloride, aluminum chloride, or boron chloride. In oneembodiment, the proton donor is aluminum chloride, or in the case thatmultiple proton donors are used, at least one of the proton donors isaluminum chloride.

In some embodiments, the proton donor contains less than 10%, less than9%, less than 8%, less than 7%, less than 6%, less than 5%, less than4%, less than 3%, less than 2%, less than 1% water, less than 0.1%, lessthan 0.01%, or less than 0.001% (wt/wt basis). In other embodiments, theproton donor contains between 1-10%, between 2-10%, between 2-4%,between 1-2%, between 0.01-2%, or between 0.001-2% water (wt/wt basis).

The Solvent

A solvent may be added to the reaction mixture. Suitable solvents mayinclude, for example, dichloromethane, ethylacetate, hexane,cyclohexane, benzene, toluene, diethyl ether, tetrahydrofuran, acetone,dimethyl formamide, dimethyl sulfoxide, acetonitrile, methanol, ethanol,isopropanol, n-propanol, n-butanol, chloroform, dichloroethane,trichloroethane, furfural, furfuryl alcohol, or supercritical carbondioxide. In one embodiment, the solvent is dichloromethane ordichloroethane. Any combination of the solvents described above may alsobe used

In some embodiments, the solvent is dry. In other embodiments, thesolvent contains less than 10%, less than 9%, less than 8%, less than7%, less than 6%, less than 5%, less than 4%, less than 3%, less than2%, less than 1% water, less than 0.1%, less than 0.01%, or less than0.001% (wt/wt basis). In yet other embodiments, the solvent containsbetween 1-10%, between 2-10%, between 2-4%, between 1-2%, between0.01-2%, or between 0.001-2% water (wt/wt basis).

Producing Substituted Furans (e.g., Halomethylfurfural,Hydroxymethylfurfural, and Furfural)

The processes described herein may be employed to produce substitutedfurans from biomass containing glycans and/or heteroglycans. In someembodiments, the processes described herein may be employed to producehalomethylfurfural, hydroxymethylfurfural, and/or furfural from biomasscontaining cellulose and/or hemicellulose. Other co-products may includelevulinic acid, formic acid, and optionally substituted alkylfurfural(e.g., methylfurfural).

a) Feeding in the Biomass and Gaseous Acid

With reference to FIG. 2, in one embodiment, gaseous hydrochloric acid(HCl) 202 and solid biomass 204 is continuously fed into fluidized bedreactor 200. In this exemplary embodiment, hydrochloric acid (HCl) 202has less than 0.001% by weight of water. In other exemplary embodiments,the amount of the gaseous acid may have different amounts of water, forexample, less than 10% by weight of water. In reactor 200, the gaseousacid and feedstock is fed into the side of the reactor. It should berecognized, however, that any combination of side inputs, bottom inputs,and top inputs may be used, depending on the type of multiphase reactorused.

Gaseous HCl 202 is fed into reactor 200 at high velocities to create anupward-flowing stream of gas that suspends solid biomass 204.Fluidization allows for uniform mixing between the acid and biomass.Solid biomass 204 is hydrolyzed and dehydrated in the presence ofgaseous HCl 202 to yield chloromethylfurfural, hydroxymethylfurfural,and furfural.

b) Product Selectivity

As discussed above, the substituted furans may rehydrate in the acidicreaction conditions to produce levulinic acid and formic acid, which areoften considered lower-valued products in the context of biofuelproduction. In some embodiments, halomethylfurfural andhydroxymethylfurfural may rehydrate in the acidic reaction conditions toproduce levulinic acid and formic acid. Thus, this possibility ofrehydration presents a challenge to commercial use of the processes forbiofuel production.

The processes described herein favor the formation of substituted furans(e.g., halomethylfurfural and hydroxymethylfurfural) over levulinic acidand formic acid. Without wishing to be bound by any theory, a reactionat higher temperatures may be driving dehydration faster thanrehydration. As observed based on the measured activation energy andother kinetic parameters, the hot gas phase system described hereinyields better product selectivity. The rate of hexose dehydration tosubstituted furans (e.g., halomethylfurfural) may be more sensitive totemperature than the subsequent rehydration to levulinic acid and formicacid, whereas the rate of rehydration may be more sensitive to acidconcentration than may be the production of substituted furans (e.g.,halomethylfurfural). Running the reaction at low acid concentrations andat high temperatures may drive product selectivity, favoring thesubstituted furans (e.g., halomethylfurfural and hydroxymethylfurfural)over levulinic acid and formic acid. These reaction conditions may beachieved in a gas phase system, as described herein.

c) Reaction Conditions

The reactor temperature range may be between the temperature at whichlittle to no dehydration of glucose would occur and the temperature atwhich pyrolysis starts to take over. In some embodiments, thetemperature in the multiphase reactor is between 50° C. and 500° C. Inother embodiments, the temperature in the multiphase reactor is between100° C. and 400° C. In other embodiments, the temperature in themultiphase reactor is between 100° C. and 350° C. In yet otherembodiments, the temperature in the multiphase reactor is between 150°C. and 300° C. In yet other embodiments, the temperature in themultiphase reactor is between 200° C. and 250° C.

The higher reaction temperatures used in the processes described hereinincreases the reaction yield because lignin may trap gaseous acids atlow temperatures. When trapped in lignin, the acid is less available toreact with the biomass; however, this inefficiency may be mitigated athigher reaction temperatures because heat drives acid from the ligninand prevents the acid from binding to the lignin. Reduced carry-over ofacid in lignin also creates process cost-savings because less acid islost for use as a solvent and/or catalyst and less acid is needed toreplenish the system. Moreover, running the processes at highertemperatures may reduce the formation of poly-halogenated phenyls.

The reactor pressure may range between 0.001 atm to 350 atm. In someembodiments, the processed described herein is performed in a vacuum. Inother embodiments, the pressure in the multiphase reactor is between0.001 atm and 200 atm. In other embodiments, the pressure in themultiphase reactor is between 0.001 atm and 100 atm. In yet otherembodiments, the pressure in the multiphase reactor is between 0.001 atmand 10 atm. In yet other embodiments, the pressure in the multiphasereactor is between 1 atm and 50 atm. In yet other embodiments, thepressure in the multiphase reactor is between 1 atm and 10 atm.

In some embodiments, the reaction mixture inside the multiphase reactorhas less than 10%, less than 9%, less than 8%, less than 7%, less than6%, less than 5%, less than 4%, less than 3%, less than 2%, less than1%, less than 0.05%, less than 0.01%, less than 0.005%, or less than0.001% by weight of water. In certain embodiments, the reaction mixtureinside the multiphase reactor has between 1% and 10%, between 2% and10%, between 2% and 4%, between 1% and 5%, between 1% and 2%, between0.1% and 2%, between 0.01% and 2%, or between 0.001% and 2% water (wt/wtbasis).

To achieve the water content in the reaction mixture described above,reactants and/or reagents (e.g., feedstock, gaseous acid, proton donorand/or solvent) with less than 10% by weight of water may be used.Desiccants may also be added to the multiphase reactor. For example, insome embodiments, molecular sieves may be added to the multiphasereactor to sequester water from the reaction mixture. In certainembodiments, reactants and/or reagents with less than 10% by weight ofwater and desiccants may be used to control the water content of thereaction mixture.

d) Solid/Gas Separation

When the gas and the solids reach the top of reactor 200 (i.e., the endof the reactor), crude reaction mixture 206 exits due to the pressuredifference inside and outside the reactor. It should be recognized,however, in reactor systems that are not driven by pressure, movement ofthe particular matter solids and their exit from the reactor may bedriven by gravity and/or mechanical means, e.g., auger systems and/oragitation.

On exit, crude reaction mixture 206 is separated into gaseous HCl 220and solid mixture 208 containing chloromethylfurfural. It should beunderstood that the solid mixture may include halomethylfurfural(corresponding to the acid employed), hydroxymethylfurfural, andfurfural. Any solid-gas separators known in the art may be used, forexample, a cyclone, a filter, or a gravimetric system. Any combinationof the solid-gas separators described above may also be used.

Gaseous HCl 220 is then passed through a desiccant to remove any water.The use of a desiccant in the processes described herein presents a costadvantage over acid separation by azeotrope shifting, which is energyintensive and expensive. Rather than relying on phase changes forseparation, which may lead to azeotropic effects in aqueous acidsolutions, the use of a desiccant allows water to change its affinityfor gaseous acid to the desiccant material, enabling more efficientseparation.

Dried gaseous HCl 222 is returned to reactor 200. Thus, the acid can berecaptured and recycled back into the system.

e) Solid/Liquid Separation

Solid mixture 208 is combined with solvent 210 to drive the reactionequilibrium towards chloromethylfurfural and hydroxymethylfurfural.Combining solvent 210 with solid mixture 208 produces mixture 212, whichcontains a solution of the products (e.g., chloromethylfurfural,hydroxymethylfurfural, and furfural) and remaining solids, which containunreacted starting materials. The components of the unreacted startingmaterials may include, for example, lignin, grit, minerals, and salts.Unreacted cellulose and hemicellulose may also be present.

Any solvent known in the art suitable to solubilize the substitutedfurans may be used. Suitable solvents may include, for example,dichloromethane, ethylacetate, hexane, cyclohexane, benzene, toluene,diethyl ether, tetrahydrofuran, acetone, dimethyl formamide, dimethylsulfoxide, acetonitrile, methanol, ethanol, isopropanol, n-propanol,n-butanol, chloroform, dichloroethane, trichloroethane, furfural,furfuryl alcohol, or supercritical carbon dioxide. Any combinations ofthe solvents described above may also be used.

Any solid-liquid separation methods known in the art, such as a filteror membrane system, can be employed to separate mixture 212 intosolution 214 (containing the products), and remaining solids 218(containing unreacted starting materials). Remaining solids 218 can beoptionally recycled and fed back into reactor 200, as shown in FIG. 2.This optional solids recycling step can improve overall reaction yield.

f) Isolating Reaction Products

To isolate reaction products 224, solution 214 undergoes distillation orany other standard separation methods known in the art. Distillationproduces separated solvent 216, which may be recycled in the solventquench, as depicted in FIG. 2. Reaction products 224 collected from thedistillation may include substituted furans (e.g., halomethylfurfural,hydroxymethylfurfural, furfural), levulinic acid, and formic acid.

In other embodiments, the isolated substituted furans can be furtherprocessed into other furanic derivatives for biofuels, diesel additives,or plastics. In some embodiments, the isolated halomethylfurfural andhydroxymethylfurfural can be further processed into other furanicderivatives for biofuels, diesel additives, or plastics. For example,chloromethylfurfural may be converted into dimethylfuran andethoxymethylfurfural.

In yet other embodiments, the isolated levulinic acid can be used to inapplications that may include, for example, cleaning solvents, couplingagents in liquid formulations, plasticizers, polyols for polyurethanematerials, polyester thermosets, thermoplastics, agricultural chemicals,polymer precursors and plastics, synthetic rubbers, pharmaceuticalintermediates, photosensitizers, precursor to other chemicalcommodities, and in cigarettes.

As used herein, the term “about” refers to an approximation of a statedvalue within an acceptable range. Preferably, the range is +/−10% of thestated value.

EXAMPLES

The following Examples are merely illustrative and are not meant tolimit any aspects of the present disclosure in any way.

Example 1: Preparation of 5-(chloromethyl)furfural,5-(hydroxymethyl)furfural, and furfural from Lignocellulosic Biomass

Lignocellulosic biomass originating from municipal wastewater from Davis(CA) is obtained and fed through a side-input into a 2000-L fluidizedbed reactor at a rate of 50 kg/minute. Gaseous hydrochloric acid is fedthrough another side-input into the reactor at a rate of 4,000 L/min.The temperature inside the reactor is approximately 220° C., and thepressure inside the reactor is approximately 15 atm.

Fluidization occurs inside the reactor, allowing for thorough anduniform mixing of the sludge and gaseous acid. After two minuteresidence times, the crude reaction mixture of gas and solids reach thetop of the reactor, and exit the reactor due to the pressure differenceinside (about 15 atm) and outside of the reactor (about 4 atm). As thegas and solids leave the reactor, the crude reaction mixture isseparated using a cyclone into gaseous hydrochloric acid and asolid/liquid mixture. A sample of the solid mixture is obtained andanalyzed by liquid chromatography-mass spectrometry (LCMS). The solidmixture contains 5-(chloromethyl)furfural, 5-(hydroxymethyl)furfural,and furfural. Additionally, some amounts of levulinic acid and formicacid are observed in the reaction mixture.

The gaseous hydrochloric acid is passed through a desiccant to removewater. This dried gaseous hydrochloric acid is fed back into thefluidized bed reactor.

The solid/liquid mixture is mixed in line with dichloromethane toproduce a mixture containing both solids, and an organic solution. Thismixture is then filtered. Samples of the retentate solids and thepermeate solution are obtained and analyzed by LCMS. The solutionpermeate contains 5-(chloromethyl)furfural, 5-(hydroxymethyl)furfural,and furfural.

The solution is transferred to a distillation apparatus to isolate thereaction products. The fractions are collected and analyzed by LCMS.5-(chloromethyl)furfural, 5-(hydroxymethyl)furfural, and furfural areobtained in high purity. The reaction also produces small quantities oflevulinic acid and formic acid.

Example 2: Production of 5-(chloromethyl)furfural (CMF) from Fructose

To a clean, dry 350 ml pressure-sealed round bottomed flask equippedwith a magnetic stir bar was added granulated fructose (0.75 g, 4.16mmol). The flask was then placed in an inert argon atmosphere and drycalcium chloride (5.6 g, 50.4 mmol) and aluminum trichloride (0.119 g,0.832 mmol) were added and the solids suspended in 1,2-dichloroethane(75 ml). The reaction mixture was removed from the inert atmosphere andgaseous hydrochloric acid (0 wt % water) was bubbled into the solutionuntil gas began to fume from the flask. The flask was then sealed andplaced in a pre-heated oil bath set to 85° C. and allowed to stir for 1hour. The reaction mixture was then allowed to cool to room temperature.The solids were filtered through filter paper, and diluted to 100 mL ofsolvent. Volumetric analysis using a CMF flame ionization detector(FID)-standard curve indicated a 2.1 mg/ml concentration of CMF. Thereaction yielded a total of 210 mg of CMF (35% yield).

What is claimed:
 1. A system for producing halomethylfurfural,comprising: a. a solid feedstock, wherein the solid feedstock comprisesbiomass, sugar, or a combination thereof; b. a gaseous acid that hasless than about 10% water by weight; c. a multiphase reactor configuredto receive the solid feedstock and the gaseous acid and provide areaction mixture comprising halomethylfurfural; and d. a solid-gasseparator selected from the group consisting of a cyclone, a filter, anda gravimetric system, wherein the solid-gas separator is configured toreceive the reaction mixture of the multiphase reactor and to provide asolid mixture and a separated gaseous acid, and wherein the solidmixture comprises halomethylfurfural.
 2. The system of claim 1, whereinthe gaseous acid is hydrochloric acid, hydrofluoric acid, hydrobromicacid, or hydroiodic acid.
 3. The system of claim 1, wherein thehalomethylfurfural is 5-(chloromethyl)furfural.
 4. The system of claim1, wherein the multiphase reactor is a fluidized bed reactor, aplug-flow reactor, an auger system or an agitation system.
 5. The systemof claim 1, wherein the multiphase reactor allows for continuousoperation.
 6. The system of claim 1, wherein the multiphase reactorallows for batch operation.
 7. The system of claim 1, wherein the solidfeedstock is dried and ground before introduction into the multiphasereactor.
 8. The system of claim 1, wherein temperature in the multiphasereactor is between 50° C. and 300° C.
 9. The system of claim 1, whereinthe pressure in the multiphase reactor is between 0.1 atm and 50 atm.10. The system of claim 1, wherein the reaction mixture comprisesbetween 3% and 8% wt water.
 11. The system of claim 1, wherein thesystem is configured to combine the reaction mixture with a solvent toprovide a mixture comprising a solution comprising halomethylfurfural,and remaining solids.
 12. The system of claim 11, wherein the system isconfigured to combine the solvent and reaction mixture in line.
 13. Thesystem of claim 11, wherein the solvent is dichloromethane,ethylacetate, hexane, cyclohexane, benzene, toluene, diethyl ether,tetrahydrofuran, acetone, dimethyl formamide, dimethyl sulfoxide,acetonitrile, methanol, ethanol, isopropanol, n-propanol, n-butanol,chloroform, dichloroethane, trichloroethane, furfural, furfuryl alcohol,or supercritical carbon dioxide, or any combination thereof.
 14. Thesystem of claim 11, further comprising a solid-liquid separator, whereinthe solid-liquid separator is configured to separate the solutioncomprising halomethylfurfural from the remaining solids.
 15. The systemof claim 14, wherein the solid-liquid separator is a filter system or amembrane system.
 16. The system of claim 1, wherein the multiphasereactor further comprises lithium chloride, sodium chloride, potassiumchloride, magnesium chloride, calcium chloride, zinc chloride, aluminumchloride, boron chloride, or any combination thereof.
 17. The system ofclaim 1, wherein the biomass includes glycans or heteroglycans.
 18. Thesystem of claim 17, wherein the biomass comprises fructose, glucose, ora combination thereof.
 19. The system of claim 1, wherein the feedstockis municipal wastewater, pulp waste, food processing plant waste,restaurant waste, yard waste, forest waste, biodieseltransesterification waste, ethanol process waste, corn stover, ricehulls, rice straw, wheat straw, paper mill effluent, newsprint,municipal solid wastes, wood chips, forest thinnings, slash, miscanthus,switchgrass, sorghum, bagasse, manure, wastewater biosolids, greenwaste, or food/feed processing residues, or any combination thereof. 20.The system of claim 1, wherein the multiphase reactor comprises: a. aninlet configured to receive the solid feedstock; b. an inlet configuredto receive the gaseous acid; and c. an outlet to provide the reactionmixture.
 21. The system of claim 1, wherein the gaseous acid has between1% and 10% water by weight.
 22. The system of claim 21, wherein thesolid feedstock has between 1% and 10% water by weight.
 23. The systemof claim 1, wherein the solid feedstock has between 1% and 10% water byweight.